Heat stress transcription factors (Hsfs) are the central regulators of defense response to heat stress. We identified a total of 25 rice Hsf genes by genome-wide analysis of rice (Oryza sativa L.) genome, including th...Heat stress transcription factors (Hsfs) are the central regulators of defense response to heat stress. We identified a total of 25 rice Hsf genes by genome-wide analysis of rice (Oryza sativa L.) genome, including the subspecies of O. japonica and O. indica. Proteins encoded by OsHsfs were divided into three classes according to their structures. Digital Northern analysis showed that OsHsfs were expressed constitutively. The expressions of these OsHsfs in response to heat stress and oxidative stress differed among the members of the gene family. Promoter analysis identified a number of stress-related cis-elements in the promoter regions of these OsHsfs. No significant correlation, however, was found between the heat-shock responses of genes and their cis-elements. Overall, our results provide a foundation for future research of OsHsfs function.展开更多
采用低温超音速等离子喷涂(LT-HVOF)在镍基高温合金基体上制备了Ni Co Cr Al YTa粘结层,使用大气等离子喷涂(APS)在粘结层上`制备了7wt%Y2O3-Zr O2(7YSZ)陶瓷层。基于动态试验即热震实验研究了粘结层的扩散氧化机制,探讨了陶瓷层的烧结...采用低温超音速等离子喷涂(LT-HVOF)在镍基高温合金基体上制备了Ni Co Cr Al YTa粘结层,使用大气等离子喷涂(APS)在粘结层上`制备了7wt%Y2O3-Zr O2(7YSZ)陶瓷层。基于动态试验即热震实验研究了粘结层的扩散氧化机制,探讨了陶瓷层的烧结及相变过程并观察了涂层的结构演变。实验结果表明:动态热循环下随着热震次数的增加,粘结层组元扩散氧化形成热生长氧化物(TGO)且厚度逐渐增加。此外,粘结层组元在温度梯度下沿陶瓷层内部裂纹向高温区扩散,最终在陶瓷层表面裂纹区域出现大量的金属氧化物,同时粘结层组元的扩散有助于陶瓷层的烧结,导致其显微硬度逐渐增大,而粘结层由于Kirkendall效应,其内部出现大量的孔洞导致其显微硬度逐渐降低。另外,陶瓷层在相变及热循环应力的作用下表面出现了大尺度的宏观裂纹。展开更多
Hydrodynamic properties and structure of strong shock waves in classical dense helium are simulated using non-equilibrium molecular dynamics methods. The shock speed in the simulation reaches 100 km/s and the Mach num...Hydrodynamic properties and structure of strong shock waves in classical dense helium are simulated using non-equilibrium molecular dynamics methods. The shock speed in the simulation reaches 100 km/s and the Mach number is over 250, which are close to the parameters of shock waves in the implosion process of inertial confinement fusion. The simulations show that the high-Mach-number shock waves in dense media have notable differences from weak shock waves or those in dilute gases. These results will provide useful information on the implosion process, especially the structure of strong shock wave front, which remains an open question in hydrodynamic simulations.展开更多
基金Project (No. 30471118) supported by the National Natural Science Foundation of China
文摘Heat stress transcription factors (Hsfs) are the central regulators of defense response to heat stress. We identified a total of 25 rice Hsf genes by genome-wide analysis of rice (Oryza sativa L.) genome, including the subspecies of O. japonica and O. indica. Proteins encoded by OsHsfs were divided into three classes according to their structures. Digital Northern analysis showed that OsHsfs were expressed constitutively. The expressions of these OsHsfs in response to heat stress and oxidative stress differed among the members of the gene family. Promoter analysis identified a number of stress-related cis-elements in the promoter regions of these OsHsfs. No significant correlation, however, was found between the heat-shock responses of genes and their cis-elements. Overall, our results provide a foundation for future research of OsHsfs function.
文摘采用低温超音速等离子喷涂(LT-HVOF)在镍基高温合金基体上制备了Ni Co Cr Al YTa粘结层,使用大气等离子喷涂(APS)在粘结层上`制备了7wt%Y2O3-Zr O2(7YSZ)陶瓷层。基于动态试验即热震实验研究了粘结层的扩散氧化机制,探讨了陶瓷层的烧结及相变过程并观察了涂层的结构演变。实验结果表明:动态热循环下随着热震次数的增加,粘结层组元扩散氧化形成热生长氧化物(TGO)且厚度逐渐增加。此外,粘结层组元在温度梯度下沿陶瓷层内部裂纹向高温区扩散,最终在陶瓷层表面裂纹区域出现大量的金属氧化物,同时粘结层组元的扩散有助于陶瓷层的烧结,导致其显微硬度逐渐增大,而粘结层由于Kirkendall效应,其内部出现大量的孔洞导致其显微硬度逐渐降低。另外,陶瓷层在相变及热循环应力的作用下表面出现了大尺度的宏观裂纹。
文摘Hydrodynamic properties and structure of strong shock waves in classical dense helium are simulated using non-equilibrium molecular dynamics methods. The shock speed in the simulation reaches 100 km/s and the Mach number is over 250, which are close to the parameters of shock waves in the implosion process of inertial confinement fusion. The simulations show that the high-Mach-number shock waves in dense media have notable differences from weak shock waves or those in dilute gases. These results will provide useful information on the implosion process, especially the structure of strong shock wave front, which remains an open question in hydrodynamic simulations.
